Cox wrote on Instagram Stories: “Happy birthday to my talented, funny friend!”
Along with her post, she shared a smiling snapshot of the two actors.
Cox and Perry rose to fame playing Monica and Chandler in the hit American sitcom. Their on-screen characters eventually fell in love and got married on the show.
“Friends” ran from 1994 to 2004, and reruns of the show continue to be a huge draw. The cast is slated to come together again for a special reunion episode.
The sitcom also stars Jennifer Aniston as Rachel Green, Lisa Kudrow as Phoebe Buffay, Matt LeBlanc as Joey Tribbiani and David Schwimmer as Ross Geller.